package com.hngy.filter;

import com.alibaba.fastjson.JSON;
import com.hngy.common.BaseContext;
import com.hngy.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 登录拦截器
 * @author LiKe
 * @date 2021/10/14 11:34
 */
@Slf4j
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

         // 1.获取本次请求的URI
        String URI = request.getRequestURI();
        log.info("拦截到请求：{}",request.getRequestURI());

        String[] URIs = {"/backend/**","/front/**","/employee/login","/employee/logout","/common/**","/user/sendMsg","/user/login",
                "/user/loginout",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };

        //2.判断本次请求, 是否需要登录, 才可以访问
        boolean check = check(URIs, URI);

        //3.如果不需要，则直接放行
        if (check){
            log.info("本次请求{}不需要处理",URI);
            filterChain.doFilter(request,response);
            return;
        }

        //4-1. 判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee")!=null){
            log.info("员工已登录，用户id为{}",request.getSession().getAttribute("employee"));

            Long id = (Long) request.getSession().getAttribute("employee");
            BaseContext.setId(id);

            filterChain.doFilter(request,response);
            return;
        }

        //4-2. 判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("user")!=null){
            log.info("用户已登录，用户id为{}",request.getSession().getAttribute("user"));

            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        //5. 如果未登录, 则返回未登录结果
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;

    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param resurl
     * @return
     */
    public boolean check(String[] urls,String resurl){
        for (String url : urls) {
            //调用路径匹配器的match方法 判断是否存在该路径
            boolean match = PATH_MATCHER.match(url, resurl);
            if (match){
                //存在 返回true 放行 不需要处理
                return true;
            }
        }
        return false;
    }
}
